This indicates that the ARP request packet needs to be transmitted over the VXLAN tunnel identified by VNI 20. Upon receipt of the ARP request, Leaf1 determines that the Layer 2 sub-interface receiving the ARP request belongs to a BD that has been bound to a VNI (20).

In the ARP request, the source MAC address is MAC3, the destination MAC address is all Fs, the source IP address is IP3, and the destination IP address is IP2. Host3 sends an ARP request for Host2's MAC address.

Similarly, a VXLAN tunnel can be established between Leaf2 and Spine if their VTEPs have reachable Layer 3 routes to one another. A VXLAN tunnel can be established between Leaf1 and Spine if their VTEPs have reachable Layer 3 routes to one another. The peer VTEP IP addresses must be specified in the ingress replication list. To allow Host1 and Host2 to communicate, L2VNIs and an ingress replication list must be configured on Leaf1, Leaf2, and Spine. A VXLAN tunnel can be established between Leaf1 and Leaf2 if their VTEPs have reachable Layer 3 routes to one another. To allow Host3 and Host2 to communicate, L2VNIs and an ingress replication list must be configured on Leaf1 and Leaf2.

On the network shown in Figure 2-11, Leaf1 connects to Host1 and Host3, Leaf2 connects to Host2, and Spine functions as a Layer 3 gateway. A static VXLAN tunnel can be created by manually specifying local and remote VNIs, VTEP IP addresses, and an ingress replication list. A VXLAN tunnel is identified by a pair of VTEP IP addresses and can be established if its VTEPs are reachable at Layer 3.

Dynamic mac address learning